Boats having internal fuel tanks must have a vent line connecting the upper portion of the interior of such tanks to atmosphere externally of the boat. It has been the practice in the past to provide an opening extending through the boat hull above the water line to which the vent line extends with a stop nut and washer engaging the inner side of the hull and a vent head being threaded on the outer side of the hull so that the vent line is fixedly held in position by the clamping of the hull between the stop nut and the vent head. The vent head is hollow to the extent that it has an internal axial bore extending partially along its length and which is connected to one or more radial bores providing the outlet passageway for the venting of fuel fumes to atmosphere. While vent heads of the foregoing type provide a fully satisfactory venting function, operation of the boat frequently permits the entry of spray into the radial passageways from which the spray particles migrate downwardly through the vent tube to the fuel tank so that there is an eventual accumulation of water in the bottom of the tank. The accumulation of water in the bottom of the fuel tank is obviously not desirable and necessitates the periodic drainage of the tank.
Therefore, it is the primary object of this invention to provide means for preventing the entry of spray into the vent head and vent line of a marine fuel tank.